For a brief period in 1971, a New Jersey based company sold novelty "x-ray" glasses through the mail via advertisements in the Marvel line of comic books. People who viewed their televisions while wearing these glasses reported seeing images that were "evil" or "from hell".
It should be noted that this phenomena occurred whether the televisions in question were turned on or off. The company quickly went out of business and investigations revealed that its address leads to a graveyard founded many decades before 1971.